Thanks Tim. Thanks El Garro.

Based on the chart, unless there's some worn London mark somewhere, to me it looks like 1896-1904 Birmingham proof.

I'll be taking it apart. Would it be expected that there are more marks inside?

Yes Sir, Drew is the mine. I bugged he and a few others with damascus safety and etching questions over the last few weeks. My first set, a two bar Elsie barrel, turned out well and the comments were thankfully very positive this last weekend. The set from the Field are next, and regardless of "proper", I think I'll go with black and white since it's not unheard of to do so on a British gun.